The present invention relates to a non-destructive inspection apparatus for inspecting large objects at high speed with a high precision, and an inspection system using such an apparatus.
An X-ray inspection apparatus, which is a kind of apparatus widely used as a non-destructive inspection apparatus, is shown in FIGS. 1a and 1b. The example shown in FIG. 1a uses a direct radiographic method of irradiating X-rays 121 generated from an X-ray source 120 onto an object 122 and picking up images on X-ray films 124 installed on the back side of the object 122. On the other hand, an example of an apparatus using no X-ray films, as indicated in JP-A-61-254837 and JP-A-58-58451, uses an indirect radiographic method in which light is emitted from a fluorescent screen 105 arranged on the back side of the object 122 in response to X-rays emitted from the X-ray source 120, as shown in FIG. 1b. The light is then amplified using an image intensifier 112, and light images are picked up by a camera 107. In these methods, a two-dimensional radiation inspection process can be carried out.
To improve the sensitivity of a conventional apparatus, it is necessary to make the fluorescent screen and image intensifier thicker to increase the sensitivity of the fluorescent screen. However, there is a problem in that these methods produce a poor resolution (the image becomes blurred).